'Although two genes have been deleted, the parasite is still alive and able to stimulate the body's protective immune system to recognise and destroy incoming mosquito-transmitted deadly parasites,' Cowman said.

This approach to vaccine development -- using a weakened form of the whole organism that causes a particular disease -- has proven successful in eradicating smallpox and controlling diseases such as flu and polio.

The human trials of the vaccine will take place at the Walter Reed Army Institute of Research in Maryland, US.

The genetically attenuated parasites to be used in the trial are being manufactured at the Walter and Eliza Hall Institute, said its release.

These findings were published in the Proceedings of the National Academy of Sciences.